SPE Library
The SPE Library contains thousands of papers, presentations, journal briefs and recorded webinars from the best minds in the Plastics Industry. Spanning almost two decades, this collection of published research and development work in polymer science and plastics technology is a wealth of knowledge and information for anyone involved in plastics.
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Conference Proceedings
BMC Composites: High Value Metal Replacement Material Alternative for Automotive Powertrain Applications
Performance requirements for underhood components are increasing
making historically used thermoplastics unsuitable for next-generation
engines. The need for higher thermal chemical and mechanical resistance
is opening the door to thermoset bulk-molding compounds (BMC)
for critical metal-replacement opportunities successful examples of
which will be presented.
Application of Digimat Micromechanical Modeling to Polymer Composites
DIGIMAT micromechanics-modeling software was evaluated to
predict the nonlinear stiffness and strength properties of glass-filled
nylon. In this particular case due to the high aspect ratio of the fibers
the properties of reverse engineered effective actual matrix properties were needed to accurately correlate both the matrix" rather than theflow and transverse to flow stress-strain behavior."
Advanced Simulation of Fiber-Reinforced Automotive Radiator End Tanks by Capturing Anisotropic Material Properties
This study aims to capture realistic anisotropic properties of a plastic
material in a structural analysis. Moldflow software has been used to
obtain the fiber-orientation details for a plastic radiator tank. This fiberorientation
output data have been transferred to the structural analysis
software (ABAQUS using commercially available interface software
(DIGIMAT). This integrated simulation technique helps in accurate
prediction of burst pressure strength of the plastic tank.
Material Characterization & Modelling of Long Glass-Fiber Composites
Modeling the stiffness of parts injection molded from long-fiber
materials is similar to yet different from behavior using short-fiberfilled
materials. This work discusses the effects of various modeling
assumptions and methods on stiffness predictions using a coupled
Moldflow-Digimat-Abaqus analysis methodology.
Fatigue Properties of Injection Molded 33% E-Glass Fiber Reinforced Polyamide-66
This paper presents the effects of melt temperature injection pressure
hold pressure and injection speed on the tensile and fatigue properties
of 33-wt% E-glass fiber-reinforced polyamide-66. It was observed that
these process parameters had a greater influence on the fatigue properties
than on the tensile properties. Melt temperature had the greatest
effect followed by injection pressure. Both hold pressure and injection
speed had smaller but significant effects on the fatigue life.
Identification Selection & Development of Composite Test Standards - A Case Study from the Development of a Design Standard for Composites
This paper examines the identification selection and development of
appropriate composite test methods as required in the composites
design process. Examples from the development of a load and
resistance factor design (LRFD) standard for pultruded composites are
presented. The issues addressed for this case study discussion are
applicable to any segment of the composites market that is looking
to establish design procedures or develop design standards.
Study of Braided Composites for Energy Absorption
The goal of this research project was to provide data to build FEA
tools and to improve the understanding of braiding technology in
order to expand predictive abilities for post-yield behavior of carbon
fiber products braided with multiple hybrid fibers.
Mesoscopic Finite Element Simulation of the Compression Forming of Sheet Molding Compound Woven-Fabric Composites
This paper describes a mesoscopic approach of using beam and shell
finite elements to model the forming of composite parts using an
SMC woven fabric. Nonlinear constitutive models are implemented
in ABAQUS/Explicit via user-defined material subroutines to describe
the shear and tensile mechanical behavior of the woven fabric.
Both single-ply and multiple-ply layups are modeled.
An Investigation of ‘Green’ Class-A SMC
Saturated- and unsaturated-polyester resins containing glycols made
from renewable or recycled sources are being developed as a way
to become less dependent on petroleum-based glycols. In this study
SMC performance of standard-density Class A automotive SMC
containing polyester resins produced from petroleum-based glycols was
compared to standard-density Class A automotive SMC containing
polyester resins produced from renewable-source glycols. The evaluation
included processing aesthetics and adhesion performance. Finally a
new low-density Class A automotive SMC containing polyester resins
produced from renewable-source glycols will be introduced.
Bio-Based Polymers from Soy Chemistry
Research on the use of soybeans to produce polyurethane polyols
unsaturated polyester resins and thermoplastic fibers has been funded
by the United Soybean Board (USB). The USB funds a wide range of
activities including research and development of new industrial products
made from soy. These developments have resulted in new patented
technology. Commercialization of this technology has resulted in the
production of unsaturated-polyester resins for fiberglass-reinforced
composites and urethane polyols for polyurethane foams. The commercial
applications of these bio-based polymers are found in a wide range
of applications in the transportation markets.
Epoxy Thermosets Modified with Novel Nano-Scaled Self-Assembled Block Copolymers: Toughening Mechanisms and Extension to Composites
A unique approach to toughening thermosets has been identified by
introducing small amounts of amphiphilic block copolymer. The result
is a good viscosity-Tg-toughness balance. In this work the fracture
behavior of these modified epoxies was carefully studied in an attempt
to understand the toughening mechanisms that exist. The findings
suggest that cavitation in even these nano-sized spherical micelles is the
primary mechanism of toughening. These findings were also found to
be a strong function of the cross-link density of the host network with
higher levels of plastic deformation at the crack tip being observed in
the low-cross-link density systems. Glass-fiber-reinforced composites
made with epoxies modified with these toughening agents were found
to have improved fatigue resistance.
Zero-Emission Acrylic Thermoset Technology
In today’s environment there is an ever-increasing desire to ‘circle the
square’ reaching high-performance durability light weight and manufacturing
flexibility without increasing and even trying to lower overall
system costs. This presentation will discuss a new enabling technology
platform engineered towards these ends: cross-linked thermoset acrylics.
These are non-flammable zero-emission systems that contain no volatile
or hazardous components at any stage of their life cycle. They are easy
to use in molding processes and ideally suited for today’s ‘greener’ lightweight
automotive composites. Their application in natural fiber
composites will also be outlined in the presentation.
Long-Fiber Reinforced Thermoplastic LFT-D & Thermosetting D-SMC Processes for Lightweight Parts Production - Trends & Recent Applications
The direct process of producing long-fiber-reinforced thermoplastics
(LFT-D) is highly innovative and economical for producing semi-structural
and structural components as well as cosmetic parts with grained
surfaces. The advanced plastic-hybrid developments with tailored LFT
and E-LFT technologies fulfill crashworthiness requirements. Similiarly
the direct processing of fiber-reinforced thermosetting materials – direct
strand molding compound (D-SMC) – is focused on the reproducible
manufacturing of the compound resulting in a constant part production
at a high level minimizing material costs and expensive post-mold operations
and paint processes as well as reducing logistical costs. The high
flexibility in composing the recipe in selecting the resins fillers and reinforcements
result in the high degree of freedom of this process.
Development of an Adhesive-Primer for Polypropylene Composites
Joining is often one of the critical steps in the fabrication of composite
products. However the low polarity and inert characteristics of
polypropylene composite surfaces cause many problems in the assembly
of these composites with dissimilar materials. In order to overcome the
adhesion issues an epoxy-based primer was developed and the compatibility
of several commercial adhesives with the primer was evaluated.
Results showed very-good lap-shear strength of up to 15 MPa with
substrate failure. The performance of the primer was also evaluated
between -30 and 80°C and after conditioning in humidity. While lapshear
strength decreased with increasing temperature it remained
unchanged after conditioning. Finally different practical approaches to
apply the primer film to a polypropylene continuous-fiber composite
were investigated including techniques to apply the primer during and
after composite consolidation.
Electrically-Heated Moulds of CRP Composite Materials for Automotive Application
The moulding system FIBRETEMP describes a procedure to heat
moulding surfaces efficiently with a consistent distribution of temperature.
The heart of this invention the use of carbon fibres to conduct
electricity as well as integrating the heating element and the structure
within the surface to be heated. These moulds are highly energyefficient
and extraordinarily dimensionally stable while also being
produced at low cost. This technology has already been proven in
manufacturing composite parts and has nearly halved cycle time for
some applications due to its efficient heating characteristics.
Fatigue & Vibration Response of Long Fiber Reinforced Thermoplastics
While numerous advances have been made in the manufacturing
methods of long-fiber thermoplastics (LFTs) their dynamic response in
terms of fatigue and vibration damping has been a subject of limited
study. There is presently no standardized design information for a
composites / automotive designer for use of LFTs in situations of longterm
fatigue and vibration. The behavior of E-glass fiber / polypropylene
LFT composites has been characterized for their fatigue behavior and
vibration response in the present study. The work provides an understanding
of the influence of extrusion / compression-molded long fibers
and the fiber orientation that is generated during their processing.
Results will be useful to designers in accounting for fatigue life and
damping factors.
Automotive Thermoplastic Composites...Industry Structure & New Technologies Respond to a Global Recession
The deterioration of macroeconomic conditions has severely impacted
automotive production and the autoplastics supply chain. Thermoplastic
composites – especially long-glass-fiber versions – will benefit from
these conditions via the development and implementation of new resin
and compound technology as well as advances in fabrication technology
adapted to the requirements of a new automotive paradigm and new
applications. Our outlook is for gains in high-performance long-glass
(and other fiber) reinforced-PP compounds in competition with shortglass
and mineral-filled compounds.
Structural Thermoplastic Composites: Filling the Gap between Stamped Steel & Molded Composites
For over 50 years the auto industry has been gradually replacing steel
with plastics and molded composites. Substantial progress has been
made particularly in applications where significant parts consolidation
is possible using composites. The need is greater than ever for further
substitution of composites for steel but large performance gaps
between steel and composites limit the rate of progress. Current
gap factors include: stiffness and strength molding thickness process
cycle time ability to weld to steel and cost. This presentation will
address approaches for eliminating each of these gap elements for
non-appearance parts using a systems approach based on new
thermoplastic composite technologies.
Latest in Additive Developments for Long Fibre Reinforced Polymers
Composite parts made from long-fibre-reinforced thermoplastic (LFT)
material systems are known for their high impact and tensile strength.
And due to the benefits of the outstanding price to performance relationship
of the in-line compounded (ILC) direct-LFT (LFT-D) technology
used for production of composites based on the use of polypropylene
and glass fibres it has achieved consistently more applications in the
automotive industry. But LFT-based automotive applications are mainly
used for parts with large surfaces which can contribute significantly to
the total amount of VOCs and odor inside a car. The current work
explains a feasible approach of using commercial additives – provided as
a complete system – in combination with VOC- and odor-reducing
additives to further enhance the mechanical and outgasing properties of
the PP / GF composites produced by LFT-D / ILC technology.
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